Lawang Sewu is Semarang's most recognized landmark — a grand Dutch colonial building completed in 1919 as the headquarters of the Netherlands Indies Railway Company. The name means "thousand doors" in Javanese, a reference to the building's hundreds of tall, arched windows and doors that give it a maze-like quality from the inside.
The building is best known for its beautiful stained-glass windows, which depict scenes from Dutch colonial life and Javanese mythology. The ground floor halls are impressive for their scale and the quality of the restoration work, which was completed in the early 2010s after decades of neglect. A small museum on site covers the history of Javanese railways.
During the Japanese occupation in World War II, Lawang Sewu served as a military headquarters and prison. The basement cells were used to hold Dutch and Eurasian prisoners. Tours of the underground section are available, though the atmosphere can feel exploitative of a grim history. The main building and gardens are worth visiting regardless. Admission is charged.